MathGeometry & TrigonometryMedium frequency
SAT Math: Angles in Polygons
22+ practice questions in Praczo
What you need to know
The concept, explained
- 1
The sum of the interior angles of any polygon is (n - 2) * 180, where n is the number of sides.
- 2
For a REGULAR polygon (all sides/angles equal), one interior angle is [(n - 2) * 180] / n.
- 3
The sum of the EXTERIOR angles of any convex polygon is ALWAYS 360°, regardless of how many sides it has.
- 4
For a regular polygon, one exterior angle is simply 360 / n.
Common mistakes
- ✗ Using the interior angle sum formula when the question asks for exterior angles.
- ✗ Assuming an irregular polygon's angles are all equal when setting up an equation.
Try a sample question
SAT-style practice
What is the measure of one interior angle of a regular hexagon?
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